Probably the best known type of adjustable wrench is known as the CRESCENT wrench, manufactured by the Cresent Tool Co. of Jamestown, N.Y. The CRESCENT wrench includes a fixed jaw forming an integral part of the wrench handle, and an adjustable jaw disposed below the fixed jaw and adjustably connected to the wrench by an interconnected rack and gear mechanism to raise and lower the adjustable jaw by rotation of the gear. Even the occasional mechanic who has used the typical, presently existing adjustable wrenches has experienced major drawbacks to the adjustable wrench. Because of an imperfect connection between the rack and gear mechanism, the adjustable jaw of the adjustable wrench has some slop or play inherent in each setting. Once the lower jaw is tightened around the workpiece in an attempt to eliminate any downward movement of the adjustable lower jaw upon turning of the wrench handle, generally it is found that the lower jaw has some rotational movement upon wrench handle turning eventually causing an imprecise fit of the jaws around the workpiece and sometimes causing stripping or rounding of the flat wrench engaging surfaces of the workpiece. Further, often it is necessary to loosen the gear setting to remove the adjustable wrench from the workpiece when in close quarters where 360.degree. rotation is not possible so that the wrench has to be removed and repositioned for further tightening or loosening of the workpiece. Because of these drawbacks, the skilled mechanic utilizes wrenches having fixed workpiece engaging jaws whenever available and, more particularly prefers fixed jaws attachable to a ratchet drive handle when in close quarters so that wrench removal and re-positioning is not necessary for complete tightening and loosening of the workpiece.
The following patents disclose a clamping member attached to an adjustable wrench in an attempt to eliminate the play between rack and gear to provide a positive locking of the wrench jaws and eliminate accidental wrench slippage: Siegrist U.S. Pat. No. 1,866,426; Brady U.S. Pat. No. 1,877,642; Justice U.S. Pat. No. 2,069,582; Michalka U.S. Pat. No. 2,160,977; Bachli et al. U.S. Pat. No. 2,979,977; Popper et al. U.S. Pat. No. 3,251,251, Schrader U.S. Pat. No. 3,340,753; and Hudson U.S. Pat. No. 4,094,215.
The Romak U.S. Pat. No. 3,766,810 eliminates the rack and gear assembly and provides a simple threaded bolt tightened into a threaded female aperture in one jaw to eliminate slop or play in jaw positioning around the workpiece, in a device for rotating a slotted sleeve in a tie rod assembly. Further, to eliminate the necessity for removing and repositioning the device when in close quarters, the four corners of the Romak device are provided with welded nuts for attachment to a standard open ended wrench. One problem with the Romak device is that the jaw tightening bolt first must be tightened to secure the jaws of the device in position securely engaging the workpiece and then the wrench must be removed from the bolt and re-positioned on the corner welded nuts for turning the device. It is very time consuming to first completely tighten the bolt to secure the jaws into position and to completely loosen the bolt to remove the device. Also, if the Romak device is left on the tie rod assembly, it may interfere with the vehicle's turning ability and will not fall off of the vehicle. Another problem with the Romak device is that the initial bolt tightening to secure the jaws in position on the tie rod sleeve causes pinching of the sleeve against the internal threaded rod, thus interferring with initial sleeve spreading and penetration of penetrating oil or other thread loosening composition. Further, the Romak bolt is capable of slipping out of an enlarged slot in one jaw if extreme torque is needed to begin turning the workpiece.
The device of the present invention eliminates all of the above-described disadvantages in adjustable wrenches by providing a tool or device having an adjustable jaw capable of both tightening and jaw rotation by rotation of a gear member. Torque is applied to the jaws and therefore the workpiece from torque applied to the gear member to achieve simultaneous jaw tightening and jaw rotation thereby assuring the most tenacious jaw gripping onto the workpiece when the most torque is applied to tighten or loosen the workpiece. In accordance with an important feature, when most torque is applied to the device of the present invention to initially loosen the workpiece, the device most tenaciously grips the workpiece to avoid slippage.